class1 = {1:'zhangsan', 2:'lisi', 3:'wangwu'}
print(type(class1))

print(class1.__getitem__(1))  #方法调用
print(class1[1])              #语法蜜糖

class2 = {'zhangsan':[202001, 80,100], 'lisi':[202002], 3:'wangwu'}
print(type(class2))
print(class2['zhangsan'])
print(class2[3])

class0 = {}
class2 = class0.fromkeys([1,2,3],'noname')
print(class2)

s = class1.get(100,'not find')
print(s)

s = class1.pop(100,'not fins)
print(s)                